Chuck



Dec. 8, 1925.

Filed Oct. 26. 1920 O. GARRISO N CHUCK INVENTOR @93mm Patented Bec. 8,1925.

ORLANDO GARRISON, 01E` DAYTON, OHIO.

` a f CHUCK.

Application ied Uctober 26, 1920.

To all whom it may concern:

Be it known that I, ORLANDO GAnnisoN, a citizen of the United States,residing at Dayton, in the county of Montgomery and State of Ohio, haveinvented certain new and useful mprovements in Chucks, of which thefollowing is a specification.

My invention relates to chucks and more particularly to gear chucks,especially adapted for automatically centering and holding helical gearsor worms, but which with modification of the engaging means, butemploying the same general mechanism and mode of operation, can beadapted to other chucking` purposes.

The object of the invention is to simplify the structure as well as themeans and mode of operation of such devices, whereby they will not onlybe cheapened in construction, but will be more efficient in use,accurate and uniform in operation, easily controlled and unlikely to getout of repair.

A further object of the invention is to provide chucking means whichwill engage a helical gear or worm upon the pitch diameter intermediatethe convolutions of the thread or teeth, thus centering the gear inrelation with its pitch diameter, rather than in accordance with theroot or crown of the tooth or thread, which may not be accuratelyformed.

A further object of the invention is to provide means for uniformly andsimultaneously actuating` the gear engaging mem bers. whereby they willengage with, substantially uniform pressure, and to further provideadjusting means whereby the pressure will be equalized, betweendifferent sets of work holding elements.

lith the above primary and other incidental objects in view as will morefully appear in the specification, the invention consists of thefeatures of construction, the parts and combinations thereof,and themode of operation or their equivalents, as hereinifter described and setforth in the claims.

In the accompanying drawings, in which 'the preferred, but notnecesarily the only einbodin'ient of the invention, is disclosed, Fig. lis a front view of the assembled chuck lbrmingl the subject matterhereof, partly broken away, showing` a worm gear engaged therein. Fig. 2is a transverse sectional view of the assembled chuck. Fig. Sl is adetail section] view showing one of the work engaging plungers in itsretracted Serial No. 419,637.

or inoperative position, and the adjusting means for the severalmembers. Fig. 4 is an exterior lateral view of the chuck, illustratingthe adjusting gearing. Fig. 5 is a detail sectional view of one of thecam rings, removed from the chuck. Figs. 6 and 7 are detail views ofcontact or bearing shoes for the reciprocatory plunger. Fig. 8 is adetail sectional view of a modification of the construction shown in thepreceding figures, wherem but a single series of work engaging elements,and a single cam ring are employed.

Like parts are indicated by similar characters of reference throughoutthe several views.

The present invention contemplates an annular head having therein aplurality of radially disposed longitudinally movable plungers, whichare preferably though not necessarily arranged in two series. Theplungers are spring retracted outwardly, and are forcibly projectedinwardly in unison by means of a revoluble cam ring surrounding theexterior of the head. In the event that two series of plungers areemployed, each series is provided with a separate cam ring, andadjusting means common to both rings is provided for effecting uniformadjustment of the plunger.

Referring to the drawing, l is an annular head, having therein a seriesof radially disposed holes or bores 2. The successive radial holes l2are'edset in relation with each other in the axial direction of the an*nular head l, to agree with the pitch of the worm or other helical workbody 3 to be centered and supported. Mounted in each. of the radialholes 2 for reciprocatory movement `in a radial direction is aplunger 4,having a sliding bearing in a sleeve or bushing 5, pressed into theinner end of the holes 2, and at its outer end having a somewhatenlarged head 6, having bearing engagment within the bore 2. interposedbetween the inserted vbushing and the shoulder of the head '6, andsurrounding the plunger 4 is a helical retracting spring 7, which bearsat one end upon the bushing 5 and on the opposite end upon the head 6,tending to actuate the plunger 4 outwardly. At its inner end the plunger4 is provided with a tapered extremity 8, the inclination or divergenceof which agrees with the angle of the thread or teeth of the worm 3 tobe engaged. The plungers 4 are of dierent length and the taperedextremities 8 are differently proportioned to agree with the size andcharacter of the Work 3 to be held. The plungers 4lbeing radiallydisposed at different points throughout the length of the screw sleeve.it Will be understood, are also located with special reference to theparticular size and character of the Worm gear to be operated upon. Thebushings 5 projectinwardly beyond the end of the bore 2, and are screwthreaded to receive a compression cap 9, enclosing a collar 10 otpacking); mater'al surrounding the plunger Lil intern'iediate thc cap 9and the endsl of the bushings 5. This cellar 10 of packing ma terialserves to exclude water, ,grit and foreign material from the plungerbearings, and to retain lubricant therein. To prevent rotation of theplungers 4f the bore 2 is preferably provided With a laterally disposedcommunicating' groove 11, engaged by a spline or stud 12, projecting'from the head G.

The head 6 oi' each of Jthe plunejers is formed With a terminal concavesocket or seat in Which is located a substanti ally semisphcricalbearing' shoe 13. As shown in the drawing', these bearing` shoescomprise truncated balls or spheres one side ot which is ground oli", tothe extent of from onefourth to one-third ot the diameter to aiiord aplain or 'Hat bearing' tace. This truncated spherical bearing memberaccurately tits with the socket or recess in the end oi' the plunger. Toafford such accurately iitted bearing' socket, the plunger head 6 iscounterbored to approximately the desired depth and a hardened ball ofthe same diameter as the contact member 13 is then pressed thereinto,under heavy pressure prior to the hardening of the plunger. Such stepis, however, merely an incident of manufacture, and may be varied oreliminated Without departing' -from the invention. rlhe truncatedspherical bearing shoe 13 thus has a universal bearing, enabling it tovariously adjust itself Within its socket. Without affecting' theplunger b v such adjusting` inovement.

To control the movement oit the plunder 4L, there is provided about theexterior ot' 'the annular head 1, a revoluble cam ring' 1-l, having'therein a series of cam depressions 15. ln the drawings, these cam faces1,5 have been shown as flat or straight in contour, and substantiallytangentially arranged in relation with the inner circumfern ence of thecam ring'. These cam faces 15 are located Within the interiorcircumference of the cam ring in such relation as to simultaneouslyengage the bearing' shoes 13 of the different plunggers pertaining' tosuoli ring' in like relation. The flat tace ot the truncated sphericalshoe 13 bears against the flat cam face 15 ol the cam rino', therebyallording a Wide uniform bearing surface, of

located about the exterior oi the ai head 1, in reverse relation. andbe; r one i [he 'v spiral or helical allocation ot 'he piunn'crsilol'lset in the axial dirciiftion off the head l .in relation with eachother neces itaies that one or more of such plungcrs ivnl or.' f thecontacting` p :es olf the rcspec" rings. Such mcdially located plan'shown at the top in 2 Will reta. cient operative onder/'ement with thctace 15 of one ot aid rings to insure nis proper operation, hut willproject laterally somewhat beyond the inner face of hc ring intojuxtaposition to the second cani rirng lll. 'llo prevent intcrlierenccin such instaiices, the cam rings i .1 are provided with clearancespaces or tgrooves lo, in their inner or adjacent races, at pointscoincident with the location of pluiig'crs of the second sedes or thosepcrtaini t' the opposin; cani rings. These cam ,grooves or spaceL li",are ot sullicient length to permit the partial rotation of the cam riniri'iecessarv to actuatc the plungers controlled n with interference withvthc plungg'rrs of the secon-d series.

The cam rings l-I- may he retained in po" sition about tl c periphery ofthe hond hf.' any suitalile retaining' means whif'b leaye the ring; andhead tree l'or reiaivo rotary movement. ln the present insl..1uv.i,there have beci'i shown a series oi' bulons or colla-rs 1i", located inspaced relation ad jacent to thc periphcr)Y oi' the annular head 1,and.overlapping the cam rino; l. 'hiw--e buttons or collars Il arcoppositcl disposed as shown in Fig. 2, and are ii err-:mnected by sere's or studs 18 cr-:tending` thru suitable holes in the head i.lnrrn1cdiately disposed iu difieren-t radial positions are counter-boredholes 1), exteinling transversely thru the l cad l bj.' which the chuckmay be secured to a tace plate, a work table or other suitable support.

rlhe cam rings 14 may he adjusted by manual eif'li'ortas by spanncrs orother n'ieans for rotating; the cani ring', but as a convenH icnt andellicient adj` i o' means by which uni torni press may he ,ffraduail-yeffected. there has been provided upon the cterior or peripheral 'faceof one ol' he cam rinfrs lll a short segment bar 20, containing gearao'ainf-'it the other as shown in li gi' ii.

i. wir i il'.

teeth, while in the opposing cam ring 1+i, at a correslicnding point,there is provided a socket 2l, to receive the pilot stud 22 of a gearpinion 2?) carried upon a hand lever 2st. rlhe socket 2l is preferablyprovided with a hardened bushing 25. The gear pinion 23 is fixedlymounted upon the hand lever 2li, and when the pilot stud 22 is engagedwithin the socket 2i, the teeth of the pinion 23 will inter-mesh withthe segmental gear rack 20 upon the second cam ring. In thisconstruction, either cam ring is capable of movement independent of theother. Upon the rotation of the gear pinion 23, the gear pinion maytravel over the segmental rack 20, carrying with it the cam ring 14:containing the socket 2l., with which the pinion is engaged, or in lieuthereof, the pinion carrying ring may temporarily remain at rest, andupon rotation of the pinion the ring carrying the gear teeth 2O will berotated, projecting the segment-al rack bar past the pinion. The cam-rings 1li having the least resistance will be the :first to move, andwhen the plungers conn trolled thereby have been advanced intoengagement with the work to afford resistance greater than that of thesecond cam ring, the latter will then rotate in relation with the firstring until the pressure exerted by the plungers carried by therespective ring is equalized, whereupon further adjustment of the gearpinion will effect a simultaneous differential movement of the cam rings14, sufficient to firmly set the respective plungers t against the Work3 with uniform pressure.

.inasmuch as these chucks are frequently used upon grinding machines, inthe presence of fine grit and water, the cam rings 14e are accuratelyfitted to the head, and to further insure exclusion of Water and grit,the contact faces are provided with minute oil grooves or channels 26,which insures a uniform distribution of lubricant which will excludewater or moisture from the joints. As before mentioned, the water andgrit is excluded from the plunger bearing by means of the packing collarl0.

ln Fig. 7 there is shown a modification of the bearing shoe i8, whereina cylindrical roller like member '13 l'laving a flattened face isprovided in lieu of the truncated spherical bearing shoe 125. lt will beobvious that in such construction in lieu ofthe spherical or concavesocket, the end of the plunger would be provided with a transversesemicireular groove to receive the modified form of bearing shoe.

ln Fig. 8, there is shown a modified construction employing but a singlecam ring in lieu of the construction heretofore described.. In suchmodification the annular head l is provided with a peripheral flange 28,against which the cam ring bears. The

construction is otherwise as before described, except that in suchinstance, all of the plungers il are controlled by the single cam ring.In such construction one element of the actuating gearing is carriedupon the peripheral flange 28 and the other element upon the revolublecam face.

To accommodate the plungers 4e to slight variations of the worm due toshrinkage or warping in hardening or other slight inaccuracies ofmanufacture, the bearing bushings 5, thru which the plungers 4reciprocate, are made with a loose fit, whereby the plunger is allowed aslight floating action within the bearing bushing by which it mayautomatically adjust itself to compensate for such variations. In,practice this clearance provided has been but five thousandths of aninch, which permits a deviation of two and one half thousandths of. aninch in either direction. This capability for compensation is found tobe quite desirable for the usual character of standard production,although if every worin operated upon is very accurately cut and groundto size, such play of the plunger will be unnecessary.

From the above description it will be apparent that there is thusprovided a device of the character described possessing the particularfeatures of advantage before enumerated as desirable, but whichobviously is susceptible of modification in its form, proportions,detail construction and arrangement of parts without departing from theprinciple involved or sacrificing any of its advantages.

While in order t0 comply with the statute the invention has beendescribed Iin language more or less specific as to structural features,it is to be understood that the `invention is not limited to thespecific deH tails shown, but that the means and construction hereindisclosed comprise but one of several modes of putting the inventioninto effect, and the invention is therefore claimed in any of its formsor modifications within the legitimate and valid scope of the appendedclaims.

Having thus described my invention, I claim:

l. In a chuck of the character described, an annular head, a pluralityof radially disposed longitudinally movable plungers carried by saidhead, said plungers being offset in relation one with another in theaxial direction of the annular head to form a helically arranged series,and means for simultaneously reciprocating the plungers.

2. In a gear chuck, an annular head, a plurality of radially disposedlongitudinally movable plungers carried by the head, said plungershaving conical heads shaped and proportioned to agree substantially withthe -ndentations of the gear within which Gli they engage approximatelyupon the pitch line ot the gear with clearance between the ends ot theplungers and the bottoms of the indentatiens, and means torlongitudinally adjusting said plungers.

In a chuck ot the character described, an annular head, a plurality ofradially disposed reciprocatory plunger-s carried by said head, saidplungers being otl'set in relation with one another and separated intotwo helically arranged series, and independent actuating means 'for theplungers oi.l each series.

Ll-. In a chuck et the character described, an annular head, a pluralityet radially disposed rcciprocatory plungers carried by said head, saidplungers being otset in relation with one another and separated into twohelically arranged series, two independently rotatable adjusting ringsmounted upon said head, each ot said rings having operative engagementwith the reciprocatory plungers ot one series, whereby the plungerspertaining` to each series are adjusted Iindependent oli the plungers otthe other series by the relative rotation ot the head and adjusting ringpertaining to such series.

5. In a chuck of the character described, an annular head, a pluralityot radially disposed reciprocatory plungers arranged in a helicalsuccession, and actuating means tor the plunger-s by which a portion ofthe plungers may be simultaneously reciprocated independent of theremaining plungers and tor subsequently reciprocating such remainingplungers.

6. In a worm chuck of the character described, an annular head, aplurality of radially disposed reciprocatory plungers carried thereby,said plungers having tapered extremities to be projected radiallybetween adjacent threads ot the worm gear and so shaped and proportionedas to engage the worin gear thread approximately at the pitch diameterot the worm gear, and means to reciprocate said plungers.

7. In a worm chuck ot the character described, an annular head, aplurality ot conical reeiprocatory engaging elements disposed inditl'crent radial directions and carried by said head, the angularityol' said conical elements being substantially in agreement with theangularity ot the Worm threads and adapted to engage said threadsapproximately upon the pitch line of' the worm gear, and means tosimultaneously advance the conical elements into engagement with theworm gear to be held.

8. In a worm chuck ot the character described, an annular head, aplurality ot worm engaging elements disposed ditterent radial directionsand oiiiset axially in relation with the head to agree with the helicaldirection ot the worm threads, the engaging ends of said elements beingshaped to enter between adjacent threads of the worm gear which theyengage approximately upon the pitch line therco't, and means ttorsimultaneously actuating the engaging elements into engagzgement withthe worin gear to be held.

9. In a holder tor helical gears and the like, a supporting member, aseries ot radially disposed truncated conical studs projecting therctromwith their apeXes directed inwardly, said studs being shaped andproportioned to engage within the indentaticiis et the gearsubstantially upon the pitch line ot the gear teeth.

l0. In a holder Ytor helical gears and. the like, a supporting member, aseries of inwardly directed radial studs, located in spaced relation, ina helical succession agreeing with the helical pitch ot the gear andcontoured Yier lateral engagement with the teeth of the gearsubstantially upon the pitch line only thereof.

1l. `In a holder for helical gears and the like, a supporting member, aseries of in wardly directed radially disposed studs, revolublyadjustable, each about its own axis, said studs being positioned andcontoured for engagement within the indentations of the gearsubstantially upon the pitch line thereof, and independently revolubleto compensate tor wear.

l2. In a gear chuck and the like, a supporting member, a plurality ofradially disposed inwardly directed reciprocatory plungers carriedthereby, the inner ends of the plungers being conically tapered forengagement within the indentures of a gear to be held with the teeth ofwhich the plungers laterally engage substantially upon the pitch line ofsuch gear,'and means to reciprocate the tapered plungers.

13. In a chuck for a helical gear member, an annular head, a pluralityof radially disposed reciprocatory plungers, said plungers being`arranged in a helical succession agreeing with the pitch of the gearmember to be held, said plungers being co-related into ditiferentgroups, and means for simultaneously reciprocating the co-relatedplungers ot each group independent of the adjustment of the plungers ofthe other group.

14. In a chuck, an annular head, a plurality of reciprocatory plungersdisposed in ditterent radial positions carried by said head, means foractuating the plungers, a socket formed in the outer extremity of eachplunger and a truncated spherical body seated in said socket forengagement with the actuatingmeans.

15. In a chuck, an annular head, a plurality of reciprocatory plungersdisposed in different radial positions carried by said head, means foractuating the plungers, and a bearing member interposed between theplunger and actuating means having a sub lili) stantially Hat bearingface engaging with one member and having rocking and revolubleengagement with the other member.

16. In a chuck for a helical gear member, an annular head, a series ofradially disposed reciprocatory plungers carried by the head andarranged in a helical succession substantially agreeing with the helicalpitch of the gear member to be engaged, a pair of independentlyadjustable rings, each controlling a plurality of plungers of saidseries mounted upon the head eXteriorly of the corresponding plungers,and relatively rotatable in relation therewith, and independent of thering pertaining to the other plungers, said rings having cam faces uponwhich the outer ends of the plungers abut whereby the plungerscontrolled by each ring are simultaneously actuated by the relativerctation of the head and corresponding ring and means for opposing theresistance of one ring against that of the other ring, to edect relativeadjustment of the less resistant ring to afford uniform pressure of theplungers.

17. In a chuck for a helical gear member, a series of radially disposedreciprocatory plungers arranged inea helical succession substantiallyagreeing with the helical pitch of the member to be held, a pair ofrelatively adjustable rings for actuating different plungers of theseries at different times, and operating means common to both rings bywhich the resistance of one ring may be opposed to that of the otherring to effect an equalized adjustment of the plungers.

18. In a chuck, an annular head, a plurality of reciprocatory plungersarranged in different radial positions carried by the head, tworelatively rotatable cam rings carried by the head, internal cam faceson said ring upon which the outer end of the plungers abut, each ringcontrolling the movement of a portion of the plungers independent of theadjustment of the remainder of the plungers, and means common to bothrings for rotating said rings in reverse directions in relation witheach other and with the head to effect the adjustment of v the plungers.

19. In a chuck, an annular head, a plurality of reciprocatory plungersarranged in dillerent radial positions and carried by the head, tworelatively rotatable adjusting rings mounted upon said head,independently con-v trolling the adjustment of different plungers of theplurality, a series of gear teeth carried by one of the rings, a gearpinion carried by the other ring and meshing with the said gear teeth,whereby the rotation of said pinion will effect the rotation of theadjust* ing ring which meets with least resistance relatively to theother ring to effect the adjustment of the plungers under uniformpressure.

20. In a chuck, an annular head, a plurality of reciprocatory plungersarranged in different radial positions and carried by the head, tworelatively rotatable adjusting rings surrounding the reciprocatoryplungers and upon the inner circumference of which said plungers abut,and independently controlling the adjustment of different plungers ofthe plurality, and an actuating element engageable simultaneously withboth rings to eti'ect the relative rotation of the rings.

21. In a chuck, an annular head, a plurality of reciprocatory plungersarranged in diiferent radial positions and carried by the head, saidplungers being arranged in two groups, two relatively rotatableadjusting rings mounted upon said head, each ring being positioned in aplane common with the plungers comprising one of said group, andindependently controlling the adjustment of different plungerscomprising the respective groups, and an operating lever directlymounted upon one of said rings and having direct engagement with theother ring, either of which may comprise the fulcrum for the movement ofthe other by said lever, as the resistance of said rings to rotation maydiffer.

22. In a chuk, a plurality of reciprocatory plungers arranged indifferent radial positions relative to a common center, two relativelyrotatable bodies controlling the adjustment of said plungers,concentrically arranged in relation with said common center in planescommon with a plurality of such plungers, and upon which the plungersterminally abut, and an actuating element simultaneously engageable withboth said relatively rotatable bodies for effecting their relativerotation to adjust said plungers, substantially as specified.

23. In a chuck, an annular head, a plurality of reciprocatory plungersdisposed in different radial positions, carried by said head, means foractuating the plungers and bearings for the plungers in which one ormore of the plungers have a loose float fit, whereby the plunger iscapable of a limited side play independent of its reciprocatorymovement.

In testimony whereof, I have hereunto set my hand this 15th day ofOctober A. D. 1920.

ORLANDO GARRISON.

